Objectives:To quantify the performance of combined maternal history, ultrasound and biochemistry at 11-13+6 weeks for the prediction of birthweight at term. Methods: 10733 women with a complete first trimester screening were included. Potential predictors for birthweight included maternal age, BMI, parity, smoking status, type of conception, time difference (days) between date of pregnancy based on CRL and LMP (CRL-LMP), uterine artery lowest PI (UtA-LPI), PAPP-A and bHCG (MoM) as well as abdominal circumference (AC, Z-score). Bootstrap methods were used for model selection and estimation, under an approximately uniform distribution of birthweight. A model was built to predict individual birthweight using first trimester variables. The additional value of these variables was quantified by comparing the birthweight absolute percent prediction error (APPE) given by the model to the percent error using the average weight reference provided by the Intergrowth study. Small and large for gestational age (SGA and LGA) were defined by birthweight <10th centile and >90th centile respectively. Results: The prediction model included BMI, parity, smoking status, time difference between date of pregnancy based on CRL and LMP, UtA-LPI, PAPP-A, bHCG and AC. in SGA newborns, first trimester individual birthweight predictions were significantly closer to the actual birthweight (median APPE=17% IQR=10-23) compared to population references (median APPE 24% IQR=20-30). However, in the overall population as in LGA newborns, first trimester did not improve birthweight prediction compared to the average weight reference. Conclusions: Birthweight predictions based on a combination of maternal history, ultrasound, and biochemistry in the first trimester significantly improved screening for SGA with a significant contribution of CRL-LMP. We report prenatal diagnosis of four cases with placental mesenchymal dysplasia (PMD) and review of literature. Case 1: Primigravida of 15 weeks was referred for abnormal-appearing cystic placenta on ultrasound scanning, with hypoechoic areas. Normal fetal Doppler, and abnormal maternal Doppler. We diagnosed PMD and indicated treatment with heparin and aspirin. During third trimester intrauterine growth restriction (IUGR) was found. Caesarean section was performed at 38 w, new born was IUGR fetus. Placental pathology showed PMD. Case 2: Multiparous was sent because abnormal placental cyst. Normal fetal Doppler, abnormal maternal Doppler. PMD was diagnosed, heparin and aspirin were indicated. At 24 w, fetal mesenchymal tumours were found in liver, suprarenal and abdomen, showing an accelerated growth, with normal fetal Doppler.
OP13.11A decrease in fetal movements was objectified at 28 w. and finally at 29 w, fetal was death. Placental pathology showed PMD. Case 3: Primigravida of 21 w. referred with diagnosis of IUGR and partial mole. Fetus had absent diastolic flow in umbilical artery, abnormal maternal Doppler, normal ACM, multiple cystic images in placenta and HCG-B within normal values. With this fin...
